Hi All, my Alula arrived this morning (thanks Michael) safe and sound having travelled half way around the world to here in northern France, I have inspected the contents of the blue box and am impressed with the quality and presentation of the kit so far and look forward to construction after the holiday which I will post here as I go along, so I wish all a good fest and a great new year!. keep the posts coming cheers

Great plane

I got my Alula last week and flew it for the first time 2 days ago. I had the removable wing option on it and on the 3rd throw the wing separated on launch. My fault. I thought I had it tightened properly. I guess not. Before the wing came off, it flew amazingly well. I did a loop and some gentle turns. I had 2 quarters taped to the nose in order to obtain the proper center of gravity. I have since removed them and replaced them with some small lead weights. I glued the wings on permanently so now there is no worry about them coming off and I can try some stronger launches.
Outside the wind is blowing at 40+mph so I will have to wait a day or so before trying it out again. So far, I am very pleased with the Alula.
Clyde

weight of paint?

Has anyone painted their Alula? I see almost everyone recommend not to do that, for fear it'll add too much weight, and most are using permanent markers instead. But how much weight are we talking about exactly? How much does paint weigh?

I did an unscientific test of two identical 28 sq-in sections I clipped off my Slow Stick wing tips. On one, I put two 1-in squares of 3M Extreme Packing tape, and then painted it with two coats of Krylon Fusion spray paint. Afterwards, the taped and modified section weighed 1g more than the unmodified one. I'm not sure how much the tape weighs, but that puts an upper bound of 1g per 28 sq-in on the weight of two coats of paint.

My other source of data is this thread: https://www.rcgroups.com/forums/show....php?t=1014117 Unfortunately the author never mentions the exact wing area, but it's a P-40 with a 4' wingspan, and I estimated 500 sq-in wing area. For him, painting the wing top and bottom (1000 sq-in total) with two coats added 17g to his wing, which works out to 1g per 58 sq-in.

Neither is a super-accurate measurement, but for estimation purposes, 1g per 45 sq-in seems reasonable. Given the Alula's 259 sq-in wing area, painting the entire top surface of the wing would add 5.75g or 0.2 ounces.

Most Alula designs I've seen don't paint the entire wing surface, but instead consist of stripes or other patterns with maybe 50% of the wing left bare white. If you did something similar with paint, a typical top-wing design would add about 3g or 0.1 ounce. Given that paint is probably going to look more "solid" and attractive than permanent markers, that seems like an acceptable weight penalty to me.

Just think of what needs to happen to allow the elevon to move up and down .

So yes, remove 1mm of material from the trailing edge to the hinge line. Just like you'll do on the inboard edge.
Be sure to exercise the surface at the hinge line to make sure it moves more freely as mentioned in a later step.

Cheers, Pete in Idaho

Quote:

Originally Posted by schamberlin

From the instructions, step 4: "use a hobby

knife or razor blade to trim away small 1mm sliver of foam joining control surface and wingtip on both wing panels."

Does that mean a 1mm wide sliver? How deep should I cut? I'm not supposed to cut all the way through, right?

I'm using GWS Pico's - just happened to have a couple laying around. They are about 6g, and fit in the Alula servo pockets like it was made for them - absolutely perfect.

I'd personally stay away from the ultra-lightweight servos - I've always been disappointed with the quality in the long run. The HS55's would be OK, if a little on the heavy side. But the difference between HS55's and, say, D47's is only about 4g per pair. And since that's pretty much right at the CG, there isn't any "extra" weight required to balance it. I doubt that the total weight difference would be much of a performance killer.

thanks for the reply Matt, you have backed up my thoughts so I have dug around and found a pair of esky ek2's and although they are billed as 8 gramme servos actually come out at between 6 and7 grammes on the scales this is probably because I shortened the cables for another job but they are fine for this build.
I am looking to build this thing light but without too much compromise but would like some colour and have located some graphic pens called Posca at my local arts store and they come in no less than 7 nib widths and 40 colours this afternoon I tried them on some large pieces of scrap foam and found them to be ideal, they are quite opaque, the paint is water based acrylic and it's possible to write on top of another colour without bleeding occurring also I did the before and after test with the scales and there was no appreciable weight difference despite loading the foam with paint .I feel they are worth a try so I will post my results when I have done, need to think of a design that is simple but effective and is original,not easy.

Neither is a super-accurate measurement, but for estimation purposes, 1g per 45 sq-in seems reasonable. Given the Alula's 259 sq-in wing area, painting the entire top surface of the wing would add 5.75g or 0.2 ounces.

Most Alula designs I've seen don't paint the entire wing surface, but instead consist of stripes or other patterns with maybe 50% of the wing left bare white. If you did something similar with paint, a typical top-wing design would add about 3g or 0.1 ounce. Given that paint is probably going to look more "solid" and attractive than permanent markers, that seems like an acceptable weight penalty to me.

Yes, but in my opinion with hand launch thermal planes, especially these small sizes, every gram counts. The idea is to shave grams not add grams. 5-6 grams is the weight of an extra servo. which might be OK if you're using your Alula for other things besides catching thermals. Some people like to slope the Alula more than thermal it, but I like to thermal it more and if I can shave a gram here and there it definitely helps.

schamberlin: take a look at my build. i used paint, and clear coat. wish i set up a blog. do a search for my posts. if you keep the paint around the cg, aka pretty much just the leading edge, the weight wont really matter as it will result in less nose weight. if your really worried about weight, cut some nice holes behind the cg and tape it. hopefully the foam removed will weigh less than the tape added...lol especially on the tail! maybe for my next i will do that. might look cool. someone did that on the version 1 alula, non evo with that plastic tail.

Spektrum DX5e for Alula??

Just received my first Alula for Christmas! I'd planned to use a 72MHz radio to fly it, but was suprised with the DX5e as a gift. I'm very new to RC, would love to run my Alula with this 2.4 GHz system, but suspect it's missing critical components (e.g., adjusting throws, deflections). Can anyone tell me if and how I can use the DX5e to fly the Alula? Thanks